Micrometer calipers



lin micrometer calipers.

WILLIAM HENRY CHURCILQF EneNWooD STATION, RHODE ISLAND, nssIGNoR orv joNE-'roURrIITo Lr-,RED rvoIINRrcIIANDsoN, or WARWICK, v,airone ISLAND..

` f MICRQMETER cAmPEns. i

Specification ofrLetters Patent.f 3,171, 31, 1922.(

' Applicationfiled December 10, 1919. Serial No; 343,820. y

To all 'whom t may concern:V Y Y '.1

Be -1t known that I, WILLIAM .YHENRY' Ci-rmroma citizen of the.' UnitedStates,'re siding at Edgewood Station, in the county of Providence andState of-Rhode Island, have .invented-a ,new and useful Improvement in Micrometer Calipers'of whichv the following is a specification.

fvly invention has reference to an improvement in measuring instrumentsof precision and .more particularly to an improvement 'The object of myinvention isto improve the construction of. a. micrometer caliper,whereby Athe lmicrometer, caliperv is.` in the form of compassesordividers iny which the legs are pivotly secured together at one end,

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the-freeends of the legshaving micromet'ric means for measuring andindicatingzunits of measurements, preferably by one thousandth of aninch. j

Further. objects of my invention are to improve and simplify theconstruction of such a micrometer caliper, thereby simplifying theoperation and reducing thecost of construction. f I v My inventionconsists in the peculiar and novel construction of a micrometer caliperin the form of dividers or Compasses, said micrometer caliper havingdetails of construction as will be more fully set forth hereinafter landclaimed.

Figure 1 is a face view of my improved micrometer caliper showmg thesame adjusted and fixed to form a one-meh micrometer caliper.

tend throughV the holes 9, 9 and the bar 10 is rigidly secured inplaceby thumb-nuts on the screw-threaded pins 11, 11 as shown in Figure2. Various sizes of adjusting bars may be separately used, that willpreferably adjust the caliper to a one, two, three and so on inchcaliper, as desired. Each leg`5 having transverse trunnion'holesf13, 13and onr theI face radial-lines and numerals 14 intheclamoing'memberandscrews into a fand' 6 terminates into., abifurcated end `12 i structed to have trunnions 22, 22 in the-trunivIionv holes `13, V13- in the leg 6, thel Vface of one trunnion4 havingvaradial' indicating line 23. The barrel 21 also has'on itsoutsidetheusual lines and numerals 24, lafscrew'- threaded spindle-hole 25,`fan*externally screw-threadedtaperedand split inner end 26 and wearadjusting nut 27. A micrometer spindle 28 isscrew-threaded throughV thescrew-threaded spindlev hole 25, ity extends through the barrel 21towards the anvil 32 and carries a thimble 29 which extends over thebarrel 21, and has the bevelled end 30 on which are theusual lines andnumerals 31. trunnions 3 3, v33y in the trunnion holes 13, 13 in the leg5,'the face,V of one trunnion having(y a'vradial indicating line 23 andthe leg has indicating lines and numerals 14.

My `improved micrometer caliper, as shown in Figure lis set for a oneinch micrometer and Vthe micrometer is adjusted to give a reading of twohundred and fifty one-thousandths of anfinch, which is the distancebetween the end of the spindle 28 and the end of the anvil 32. rWhen itis necessary to change the caliper into a two inch micrometer caliper,the one inch adjusting bar 10 is removed, the legs 5 and 6 spread apartthe required distance, a two kinch ad-y justing bar 10 secured in placeof the one inch' bar, as described, the barrel 21 and anvil 32 turned ontheir trunnions in the trunnion holes13, 13 until the indicating linesV23, 23 on the trunnions coincide with theV lines 2, 2 ofthe indicatinglines 14 which again Vbring the center line vof the spindle 28 intoalignment with the center line of Ythe anvil 32. The barrel 21 and anvil32 are then secured in place by tightening the clamping screws 18, 18.operations are repeated in changing the micrometer caliper into athree,four and so An anvil v32 is constructed to have easily, quickly andaccurately changed fromy a small t0 a large micrometer caliper andvice-versa, and when so changed the legs vare rigidly secured in thechanged position and the center lines of the spindle and anvil arealways in alignment with each other, thereby providing an extremelyaccurate convertible micrometer caliper.

Having thus described my invention I claim as new l. Amicrometer'caliper having two legs pivotally secured together at oneend, said legs having trunnion holes at their free ends, an adjustingbar detachably secured to Vthe legs, means for detachably securingV theVadjusting bar to the legs, a micrometric measuring means having abarrel, trunnions on the barrel rotatably supported in trunnion holes inthe free end of one ofthe legs, means for clamping the measuring meansto the leg, an anvil having trunnions rotatably supported in thetrunnion holes in the free end of the other leg and means for clampingthe anvil to the leg.

ksecuring the bar in place, a micrometric measuring means having abarrelwith trun nlons adj ustably secured in trunnion holes 1n the bifurcatedend of one of the legs, said barrel having indicating lines andnumerals,

a spindle screw-threaded through the barrel, a thimble on the spindleand having indicating lines and numerals, an indicating line formed onthe trunnion, indicating lines and numerals formed on'the end of theleg, means Jfor clamping the'barrel in the adjusted position, an anvilwith trunnions adjustably secured in trunnion holes in the b i- Iturca-ted end of the other leg, an indicatingl line formed on the anviltrunnion,indicat ing lines and numerals formed on the end of the anvilleg andi means vfor. clamping the anvil in the adjusted position. y

In testimony whereof, I have signed my name to this specication.

ii/'iLLiAM'v HENRY CHURCH.V 5

